<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <!--设置这个网页的icon图标-->
    <link rel="shortcut icon" href="./img/商家-轮胎服务.png" type="image/x-icon"></link>
    <style>
        h3{
            font-size: 40px;
            text-shadow: 2px 4px 20px red;
        }
        div{
            width: 200px;
            height: 200px;
            background-color: #000;
            box-shadow: 2px 4px 20px 20px red inset;
            /*过渡效果*/
            transition: all 5s;
        }
        div:hover{
            background-color: yellow;
            box-shadow: 4px 7px 30px 30px green;

        }
    </style>
</head>
<body>
<h3>background-size和background连写同时设置时，需要注意覆盖问题</h3>

<div>

</div>
</body>
</html>